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Take That, ARRL

Warning: This is going to be one of those
unabashedly nerdy blogitems that I occasionally commit. The
subject — frequency measurement
— is simultaneously tedious and
irrelevant, and it embodies the charm of license plate spotting while
stuck in a ten-mile traffic jam. I shall attempt to enliven this
at the very end with a linguistic observation (if I remember to) but
this is almost certainly doomed to failure, interest-wise.

The ARRL, the American Radio Relay League, is and has
been since the beginning of ham (amateur) radio the umbrella
organization for its practitioners. A very large percentage of us
join, although we are under no obligation to do so, and its magazine,
the engagingly titled "QST" is an important historical and technical
journal in our radio lives. The ARRL sponsors various activities
and promulgates the rules and dates in QST. For example, "Field
Day" is coming up, at which time hams will leave their comfortable homes
to erect antennas in public parks, farm fields, and mountain tops and
attempt to contact others so-situated over the radio. One major
contributor to the non-profit ARRL is the mosquito repellant
manufacturers association.

The majority of ARRL-sponsored activities could be
considered "social" in the sense that, as does Field Day, they involve a bunch
of hams getting together to do something. Others are social in the
sense that the goal is for hams to contact each other on the radio and
exchange information. But one activity is both solitary and
nerdish: The "Frequency Measuring Test." In the FMT, the
ARRL uses its headquarters radio station W1AW to transmit signals at
several different frequencies in the amateur radio bands, and it is up
to the entrants to measure the frequencies as precisely as they are able
to. For example, the contest announcement may say that W1AW will
be transmitting on (approximately) 1853, 3586, and 7039 kHz. The
mission would be to refine that to 1853,059.2 Hz, etc.

In order to do this, you have to have a number of
capabilities:

You have to find the signal with your receiver.
Although this is usually easy, you must contend with "band
conditions" and weak signals, not to mention possible interference
from other users who share the frequency.

You have to identify the signal. They identify
in Morse Code, so if you don't speak Morse you might pick the wrong
signal.

You have to measure the frequency of the signal as
precisely as possible. Depending on your equipment, which you
have hopefully recently calibrated, you might be limited to
measuring to the nearest 100 or 10 Hz. It actually takes a bit
of precision work to get to the nearest Hz and fraction thereof.
(A "Hz" is just a "cycle per second" in new clothes. An AM broadcast station,
e.g., 1010 WINS, transmits on 1,010,000 Hz.)

Needless to say, the FMT is one of my favorite ham (and
nerd) activities. I can sit, (alone, of course,) amongst the
glowing lights and screens of my test equipment and reduce hours of
effort and kilobucks of hardware to three or four precise numbers, each
of which agrees closely with its counterpart number measured at ARRL
Headquarters over a hundred miles from here. What's not to enjoy?
But the best part of the FMT for me was that I was able to prove the
ARRL wrong in one of their assumptions about the contest. There is
no greater nerd satisfaction than doing something that you are told
can't be done. My joy was ameliorated to some extent in that I
think the "can't be done" assertion wasn't well thought out. In
early announcements of the FMT in QST, ARRL asserted that accuracies
greater than 1 PPM weren't possible. Hah! (1 PPM is 1 Hertz
per megahertz. For example, it's "impossible" to measure the 7039
frequency to better than 7Hz. Did I mention "Hah!"?) This
surprised me when I saw it, and in later years they dropped the claim.
I'd like to feel that I contributed to their change of theory.

The Results

2002

To some extent the accuracy of measurement
depends on how strong and clear the transmitted signals are.

2003

This was my best result by far. Clear
signals and a bit of luck in that I didn't have rounding errors
count against me.

What happened in
2004 and 2005?
For whatever reason, in 2004 I was unable to hear the signals
they were transmitting. "Conditions" were extremely poor.
And 2005? I forgot!

2006

An embarrassing performance. The 7MHz
signal was very hard to hear and to measure. Note that
this year they
didn't use the higher frequencies, in which rounding errors
count for less.

As you can see, the very worst result was .26
PPM, and most were .1PPM or (much) better. As an aside, I ran an
experiment some years ago where I "measured" the frequency of WWV, the
National Institute of Standards and Technology station. NIST was
previously NBS, the "National Bureau of Standards," and their station
WWV is the definition of frequency both by law and by technology,
so when you "measure" its frequency, you're really testing your
equipment and the radio propagation path. During my experiment, I
could see their signal change by about +/- 1Hz every day as the
ionosphere changed its characteristics from day to night and back again.
If I only measured a 1Hz (.1PPM) change over a 1500+ mile path, you can
see why I was confident of doing better with the much shorter distance
to the ARRL transmitter. I have about a year's worth of WWV data from
two locations. If you think this blogitem is tedious already,
imagine how much fun you'd have reading about that! I'm saving it
for publication if I ever decide to join academia.

In summary, then, to the ARRL, I say, "Neener neener."
I would in just the recent past have said "Nyah nyah" but apparently "neener"
has replaced "nyah" as the childhood epithet of derision. I'm not
sure how this happened, although I think my first "neener" sighting was
in a Dave Barry column long ago, and it has the benefit of being
phonetically easier to digest. Or, it could be a regional thing.
Both I and the ARRL are in the Northeast, so maybe "Nyah nyah" is more
appropriate. Take that!